Systems and methods for providing a heating cycle to an after-treatment system of a vehicle

ABSTRACT

A method of providing a heating cycle for an after-treatment system is described. The method comprises initiating a pre-charge cycle of a DCDC converter and determining a temperature of the after-treatment system. In response to determining the temperature of the after-treatment system is below a threshold temperature and the pre-charge is complete, the method further comprises operating a solid-state switch to electrically connect a high voltage power source to a heating element to of the after-treatment system, and heating the after-treatment system with the heating element until the after-treatment system reaches the threshold temperature.

BACKGROUND

The present disclosure relates to systems and methods for controlling aheating element for providing heat to an engine after-treatment system,more particularly, but not exclusively, to systems and methods relatedto selectively providing a heating cycle to a catalytic converter priorto engine start.

SUMMARY

Through consumer demand and local regulation, the need for reducedengine emissions has led to engine exhaust systems that comprisecatalytic converters. Catalytic converters are a specific type of engineafter-treatment system that reduces pollutants in exhaust gases bycatalyzing a redox reaction. Catalytic converters are located downstreamof the engine within a structure/housing in the exhaust system, that isdesigned to contain and direct exhaust gases over and/or through thecatalytic converter. Like many after-treatment systems, catalyticconverters require heating up to be most effective. As the demand forcleaner emissions increases and legislation requires a reduction in thepollutants produced by internal combustion engines, solutions involvingexhaust after-treatment systems are increasingly desired.

According to examples in accordance with an aspect of the invention,there is provided a method of providing a heating cycle for anafter-treatment system, e.g., of a vehicle. The method comprisesreceiving a start trigger, initiating a pre-charge cycle of a DC-DCconverter, and determining the temperature of the after-treatmentsystem. In response to determining the temperature of theafter-treatment system is below a threshold temperature and determiningthat the pre-charge is complete, the method further comprises operatinga solid-state switch to electrically connect a high voltage powersource, e.g., a high voltage battery, to a heating element of theafter-treatment system, and heating the after-treatment system using theheating element until the after-treatment system reaches the thresholdtemperature. In some examples, the high voltage power source may beconnected directly to the heating element of the after-treatment system,or indirectly, e.g., by virtue of one or more other devices.

In some examples, the method further comprises starting an engine, e.g.,in a delayed response to the start trigger. In some examples, the engineis started after the after-treatment system reaches the thresholdtemperature. In some examples, the method further comprises providing anauxiliary power before an engine start. For example, one or moreelectrical devices, e.g., high voltage electrical devices, may beconnected to a high voltage power source (e.g., a high voltage powersource having a voltage greater than 12V, such as 48V). In someexamples, the one or more electrical devices may be configured toreceive auxiliary power from the high voltage power source prior to anengine start, e.g., after and/or in response to the start trigger, andprior to the engine start. That is to say that the high voltage powersource may supply power to one or more electrical devices, such as apower tool and/or a domestic appliance (and/or any other appropriateexternal device connectable to a vehicle), from the high voltage powersupply, e.g., prior to engine start. In some examples, the engine isstarted while the one or more high voltage devices are receiving power.In some examples, the start trigger may be at least one of a signalreceived from a key fob, a door of a vehicle opening, a signal receivedfrom a smart device application, an engine start request, and/ordetecting a proximity of a user. In some examples, the method furthercomprises closing an e-switch of a power source to electrically connectthe power source to the after-treatment system. In some examples, thehigh voltage power source is a power source of a hybrid electric vehicle(HEV), e.g., a hybrid battery.

In some examples, the method further comprises determining a pluralityof contextual factors. In some examples, an amount of thermal energyprovided to the after-treatment system by the auxiliary heat source isbased on the contextual factors. The contextual factors may be at leastone of an ambient temperature, a time since a last engine start-up, adelta temperature between the temperature of the after-treatment systemand the ambient temperature, an engine temperature, a maximum poweroutput from the auxiliary heat source, a maximum thermal energy outputfrom the heat source, a target temperature for the after-treatmentsystem, or a state of charge of the power source. In some examples, inresponse to the after-treatment system reaching a target temperature,the method comprises starting an engine.

In some examples, the method further comprises determining a state ofcharge of a high voltage power source, e.g., an energy storage device ofa hybrid vehicle. In some examples, the method further comprisesmodifying a minimum state of charge of the high voltage power source toenable a next heating cycle of the heating element. Modifying theminimum state of charge may comprise elevating a minimum amount ofcharge to be held within the high voltage power source. For example,modifying the minimum state of charge may comprise changing the energystored within a hybrid system energy storage device, such as a hybridvehicle battery.

In response to receiving the start trigger, in some examples, the methodfurther comprises initializing at least one vehicle system, such as abattery energy control module, an auxiliary device, an e-machine, or anengine control module. In some examples, the method further comprisesinitializing two or more vehicle systems in parallel. In some examples,the method further comprises, in response to the after-treatment systemreaching a target temperature, starting an engine.

In some examples, the power source, e.g. a hybrid vehicle's battery,comprises an e-switch, which can replace a conventional mechanicalcontactor found in HEVs. Accordingly, the method may further compriseoperating a pulse-width modulation (PWM) switch and/or DC-DC converter.In some examples, the eCAT comprises an additional independent switch.For example, a PWM switch or a separate, e.g., additional, DC-DCconverter, which can modulate power from the high voltage power sourceto the eCAT. In some examples, the e-switch is operable to electricallyconnect an eCAT, and/or an auxiliary device, to the power source, e.g.,after receiving the start trigger and prior to engine start.

According to a second example in accordance with an aspect of theinvention, there is provided an exhaust system suitable for use with anengine. The exhaust system comprises an after-treatment system and anexhaust control module configured to receive a start trigger, initiate apre-charge cycle of a DCDC converter, and/or determine a temperature ofthe after-treatment system, either by itself or in combination with oneor more other control modules. In response to determining that thetemperature of the after-treatment system is below a thresholdtemperature and determining the pre-charge is complete, the exhaustcontrol module is further configured to operate a solid-state switch toelectrically connect a high voltage power source to a heating element ofthe after-treatment system, and heat the after-treatment system usingthe heating element until the after-treatment system reaches thethreshold temperature.

According to a third example in accordance with an aspect of theinvention, there is provided a vehicle. The vehicle comprises an engineand an exhaust system. The exhaust system comprises an after-treatmentsystem, an exhaust control module configured to receive a start trigger,initiate a pre-charge cycle of a DC-DC converter, and determine atemperature of the after-treatment system. In response to determiningthat the temperature of the after-treatment system is below a thresholdtemperature and determining the pre-charge is complete, the exhaustcontrol module is further configured to operate a solid-state switch toelectrically connect a high voltage power source to a heating element ofthe after-treatment system, and heat the after-treatment system usingthe heating element until the after-treatment system reaches thethreshold temperature.

In some examples, the power source, e.g. a hybrid vehicle's battery,comprises an e-switch to replace a conventional mechanical contactor,such as that found in HEVs. The e-switch electrically connects an eCAT,and/or an auxiliary device, to the power source prior to engine start,which is not possible when using a mechanical contactor in somecircumstances. In some examples, the control module further comprisesclosing an e-switch of a power source to electrically connect the powersource to the after-treatment system. In some examples, the high voltagepower source is a hybrid system power source, such as a battery.

In some examples, the eCAT comprises an additional independent switch.For example, a PWM switch and/or a separate DC-DC converter, to modulatepower from the high voltage power source to the eCAT.

According to a fourth example in accordance with an aspect of theinvention, there is provided a non-transitory computer-readable mediumhaving instructions encoded thereon for carrying out a method, themethod comprising the method as described herein. In some examples, themethod comprises receiving a start trigger, initiating a pre-chargecycle of a DC-DC converter, and determining the temperature of theafter-treatment system. In response to determining the temperature ofthe after-treatment system is below a threshold temperature anddetermining that the pre-charge is complete, the method furthercomprises operating a solid-state switch to electrically connect a highvoltage power source (e.g., a hybrid system power source, such as abattery,) to a heating element of the after-treatment system, andheating the after-treatment system with the heating element until theafter-treatment system reaches the threshold temperature. In someexamples, the method further comprises closing an e-switch of a powersource to electrically connect the power source to the after-treatmentsystem

According to a fifth example in accordance with an aspect of theinvention, there is provided a method of pre-heating a catalyst of anaftertreatment system, the method comprising, in response to receiving atrigger, operating a solid-state switch to electrically couple a heatingelement to a power source prior to starting an engine to which theaftertreatment system is coupled. For example, electrically coupling theheating element to the power source may comprise: operating an e-switch,to electrically connect the power source (e.g., a HEV battery) to apower net (or power bus) of a HEV; and operating a pulse-widthmodulation switch, to modulate the power to the heating element from thepower source.

For the avoidance of doubt, the system and methods for providing aheating cycle for an after-treatment system, according to any of theexamples described herein, may be used to improve the emissions of avehicle. Whilst the benefits of the heating cycle may be described byreference to hybrid vehicles or mild hybrid vehicles, it is understoodthat the benefits of the present disclosure are not limited to suchtypes of vehicle, and may also apply to other types of vehicles, such asforklifts, trucks, buses, locomotives, motorcycles, aircraft andwatercraft, and/or non-vehicle based systems that utilize a catalyticconverter, such as electrical generators, mining equipment, stoves, andgas heaters.

These examples and other aspects of the invention will be apparent andelucidated with reference to the example(s) described hereinafter. Itshould also be appreciated that particular combinations of the variousexamples and features described above and below are often illustrativeand any other possible combination of such examples and features arealso intended, notwithstanding those combinations that are clearlyintended as mutually exclusive.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and advantages of the disclosures hereinwill be apparent upon consideration of the following detaileddescription, taken in conjunction with the accompanying drawings, inwhich:

FIGS. 1A and 1B illustrate example flow charts of similar methods forproviding a heating cycle for an after-treatment system of a vehicle, inaccordance with at least one of the examples described herein.

FIG. 2 . illustrates an example hybrid system power-up sequence, inaccordance with at least one of the examples described herein.

FIG. 3 . illustrates an example hybrid system power-up sequence, inaccordance with at least one of the examples described herein.

FIG. 4 . illustrates an example hybrid system power-up sequence, inaccordance with at least one of the examples described herein.

FIG. 5 illustrates an electrical power control system for a hybridvehicle, in accordance with at least one of the examples describedherein.

FIG. 6 illustrates an exemplary exhaust system comprising an engine andafter-treatment system, in accordance with at least one of the examplesdescribed herein.

FIG. 7 illustrates a vehicle comprising an engine and an exemplaryexhaust system, in accordance with at least one of the examplesdescribed herein.

DETAILED DESCRIPTION

It should be understood that the detailed description and specificexamples herein while indicating exemplary embodiments, are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention. These and other features, aspects, and advantages of thepresent invention will become better understood from the followingdescription, appended claims, and accompanying drawings. It should beunderstood that the Figures are merely schematic and are not drawn toscale. It should also be understood that the same or similar referencenumerals are used throughout the Figures to indicate the same or similarparts.

As discussed briefly above, current regulations on emissions standardsare requiring manufacturers of internal combustion engines to reduce theoperating emissions from the engines they manufacture. These engines areused in any appropriate type of vehicle, such as an automobile, amotorbike, a marine vessel, or an aircraft. In particular, the vehiclemay be any appropriate type of hybrid vehicle, such as a Hybrid ElectricVehicle (HEV), a Plug-in Hybrid Electric Vehicle (PHEV), a Mild HybridElectric Vehicle (mHEV) or any other vehicle having a fuel tank and aelectrified powertrain. Typically, hybrid vehicles use two or moredistinct types of means to store energy, such as batteries to storeelectrical energy and gasoline/diesel to store chemical energy. Thebasic principle of hybrid vehicles is that the different types of motorshave diverse efficiencies under different conditions, such as top speed,torque, or acceleration and therefore switching from one type of motorto another yields greater efficiencies than either one could have theirown. However, under the proposed new emissions standards in markets suchas the European Union (EU), North America, and the United Kingdom (UK),the increased efficiencies of hybrid vehicles may be insufficient tosatisfy new emission standards.

One solution to reduce the toxic emissions of vehicles is the use of anexhaust after-treatment system. Exhaust after-treatment systems aim toreduce hydrocarbons, carbon monoxide, nitrous oxide, particulate matter,sulfur oxide, and volatile organic compounds such aschlorofluorocarbons. Examples of exhaust after-treatment systems includeair injection (or secondary air injection), exhaust gas recirculation,and catalytic converters.

Electronically heated catalysts, or eCATs, are a type of catalyticconverter, which have been in use for a number of years. An eCATtypically comprises a heating element disposed within, or near to, acatalyst. However, eCATs take time to reach an optimum temperature andpeak efficiency. One solution is to preheat an eCAT to its optimumtemperature and assist with catalyst light off. The time it takes towarm up the catalyst after engine start can be critical to the successof meeting the emissions standard. Therefore, in an ideal scenario, theeCAT is preheated prior to engine start so that the eCAT is at peakefficiency and the emissions of the engine are reduced without having towait for the catalyst to warm up. In this way, the emissions can becompliant with local regulations from the moment the engine is started.

However, supplying electrical energy to power the eCAT is not possiblewith the current system architecture in HEVs, nor without a mechanism totransfer the thermal energy from the eCAT to the catalyst. For example,mHEV system architectures cannot supply the eCAT with electrical energyuntil after the engine has been started via the low voltage (e.g., 12V)system and has achieved a normal ‘running’ state. This is because thehybrid battery mechanical relay contactor must remain open until afterthe 12V system has cranked the engine, due to the risk that the currentrequired to crank the engine (discharged from the 12V system) may leadto a brief voltage drop in the 12V system that causes the high voltage(e.g., a hybrid system battery) relay contactor to chatter and arc,potentially welding it closed and damaging the engine system.

Accordingly, the systems and methods described herein address the systemarchitecture, in particular the start-up/power-up procedure of hybridvehicles, to enable hybrid battery power prior to engine start. Thesystems and methods described herein also address the mechanicalcontactor of the hybrid battery pack of the described mHEV or HEV systemarchitectures, which do not enable heating prior to the engine start(i.e., pre-heating). For the avoidance of doubt, any of, or at least anypart of, the system architectures described below may be implemented inany appropriate hybrid vehicle, and are not limited to implementation inany one type of hybrid vehicle.

In accordance with at least one of the examples described herein, thenew power-up sequence decouples the hybrid system power-up from the lowvoltage (e.g., 12V) system prior to the engine crank. In some examples,a solid-state switch enables the hybrid system to ‘power-up’ as soon asa trigger event is detected, as will be described in more detail withreference to the figures, below.

FIG. 1A illustrates an example flow chart of a process 100 for providinga heating cycle for an after-treatment system of a vehicle, inaccordance with at least one of the examples described herein. Process100 starts at step 102 when a start trigger is received. In someexamples, a start trigger may be any one or more of a signal receivedfrom a key fob, a door of a vehicle opening, a signal received from asmart device application, a signal received from an auxiliary deviceconnected to the power source, an engine start request, or detecting aproximity of a user.

At step 104, a pre-charge cycle of a DC-DC converter is initiated. Atstep 106, a temperature of the after-treatment system is determined. Insome examples, one or more other contextual factors may also bedetermined. In such examples, an amount of thermal energy provided tothe after-treatment system by the heating element is based on the one ormore contextual factors. For example, if an ambient temperature of theenvironment of the after-treatment system is very low, more thermalenergy may be needed to be supplied to the heating element to ensurethat the after-treatment system is sufficiently preheated. Thecontextual factors may comprise at least one of an ambient temperature,a time since a last engine start-up, a delta temperature between thetemperature of the after-treatment system and the ambient temperature,an engine temperature, a maximum power output from the auxiliary heatsource, a maximum thermal energy output from the heat source, a targettemperature for the after-treatment system, or a state of charge of thepower source.

At step 108, a solid-state switch is operated. In some examples, thesolid-state switch is a metal-oxide-semiconductor field-effecttransistor (MOSFET) or other suitable solid-state relay-basedtechnology. In some examples, the solid-state switch electricallyconnects a the high voltage power source. In this way, power to theheating element of the after-treatment system is provided prior toengine start. In some examples, power to an auxiliary system may also beprovided prior to the engine start. The auxiliary system may supplypower to a range of devices from power tools to domestic appliances.

At step 110, the after-treatment system is heated. In some examples, theafter-treatment system includes an eCAT and a catalyst. Theafter-treatment system is heated until it reaches a thresholdtemperature, which may be the same temperature as the most efficienttemperature of the catalyst, e.g., for a given operating condition. Insome examples, the threshold temperature may be above the most efficienttemperature of the catalyst, to allow for some cooling effects betweenending the heating of the after-treatment system and starting an engine.In some examples, the threshold temperature may be below the mostefficient temperature of the catalyst, to allow for heating from theengine exhaust to bring the catalyst up to its most efficienttemperature.

In some examples, heating of the catalyst of the aftertreatment systemmay be reliant, at least in part, upon airflow passing over the heatingelement to transfer the thermal energy to the catalyst and to protectthe element from overheating. Therefore, prior to engine start and thuswithout the exhaust gas flow of a running engine, a pump may be added tothe system to enable the transfer of thermal energy from the eCAT to thecatalyst by generating airflow in the exhaust to transfer the thermalenergy from the heating element to the catalyst. In some examples, thismay include adding a pump to the exhaust gas recovery (EGR) circuit, orutilizing (or repurposing) an e-compressor of the vehicle.

FIG. 1B illustrates an example flow chart of an alternate process 100for providing a heating cycle for an after-treatment system of avehicle, in accordance with at least one of the examples describedherein. As illustrated in FIG. 1B, process 100 may further compriseadditional steps 122 and 124. After step 104, wherein a pre-charge cycleof a DC-DC converter is initiated, the process 100 may continue on tostep 122. At step 122, a hybrid battery of a HEV is initiated. In someexamples, the hybrid battery may be in a sleep mode, therefore, at step122, the hybrid battery is woken.

After step 108, wherein a solid-state switch is operated, as describedabove, the process 100 may continue on to step 124. At step 124, apulse-width modulation (PWM) switch is operated to modulate power fromthe power source to the heating element of the after-treatment system.In some examples, the after-treatment system may comprise an additionalDC-DC converter rather than a PWM switch, therefore, at step 124, theDC-DC converter is operated. For example, electrically coupling theheating element to the power source may comprise: operating an e-switch,to electrically connect the power source (e.g., a HEV battery) to apower net (or power bus) of a HEV; and operating a pulse-widthmodulation switch, to modulate the power to the heating element from thepower source. In some examples, it is step 124 that activates an eCAT toprovide thermal energy to the after-treatment system.

FIG. 2 . illustrates an example hybrid system power-up sequence 200, inaccordance with at least one of the examples described herein. As shown,after a trigger event 210 is received, a control module 220, such as anengine control module or power control module, receives a signal thatindicates a trigger event 210 has occurred. The control module 220 maybe electronically connected to a DC-DC converter 230, an energy controlmodule 240, and an auxiliary heat source 250.

In some examples, after receiving a signal indicating a trigger eventhas occurred, the control module 220 then sends a signal to the DC-DCconverter 230 to begin a pre-charge. After the pre-charge is complete,the control module 220 then measures a temperature of an after-treatmentsystem. In some examples, the after-treatment system is an eCAT. Inresponse to the temperature of the after-treatment system being below athreshold and the pre-charge cycle completing, the control module 220sends a signal to the energy control module 240 (e.g. a battery energycontrol module (BECM)) to operate an e-switch. In some examples, thee-switch is a solid-state based relay switch, such as a MOSFET. Theclosing of the switch connects the high voltage power source to a bus ofthe vehicle, enabling the use of the vehicle's high voltage power sourceprior to the engine start. In some examples, the high voltage powersource may be a hybrid vehicle battery, such as a 48V HEV battery.

Once the control module 220 has sent a signal to the energy controlmodule 240 to close the switch and electronically connect the highvoltage power source to the bus, a signal is sent to the auxiliary heatsource 250 to provide heat to the after-treatment cycle. In someexamples, the control module 220 controls the auxiliary heat source 250and regularly measures the current temperature of the after-treatmentsystem until the threshold temperature is met. After the thresholdtemperature is met, the control module 220 enables the engine to startand the normal running mode of the engine continues. In some examples,the control module 220 commands a heating element PWM switch orsecondary DC-DC converter connected to the after-treatment system toactivate an eCAT and consume power now that the power source isconnected.

FIG. 3 . illustrates an example hybrid system power-up sequence 300, inaccordance with at least one of the examples described herein. As shown,the hybrid system power-up sequence is similar to that shown in FIG. 2 ,however an additional auxiliary device 310 is shown as alreadyinitialized. In some example, power can only be drawn from the hybridbattery once the battery e-switch is closed. Step 310 may includeinitialization of an auxiliary device. However, the auxiliary device maybe unable to draw power as the hybrid battery is yet to be connected tothe hybrid system, which may occur once the battery e-switch is closed.The auxiliary device 310 may be any device that can operate directlyfrom the hybrid energy source or any device that would operate after aninverter converts the direct current (DC) supply to an alternatingcurrent (AC) supply, such as power tools, domestic appliances, or thelike. The auxiliary device 310 draws power from the high voltage powersource when the rest of the system is offline. That is to say that, theengine is not running and a trigger event has yet to be received by thesystem (e.g., prior to engine start).

In some examples, the solid-sate switch is closed 240 and the auxiliarydevice 310 can draw power prior to the engine after-treatment heatingcycle (and engine start). In some examples, the auxiliary device 310 candraw power and be used nominally in parallel to the after-treatmentcycle 250.

In some examples, a state of charge of a high voltage power source isdetermined. In some examples, the auxiliary device 310 reduces the stateof charge (SOC) of the high voltage power source to a level approachingthe minimum SOC required to enable the heating cycle of theafter-treatment system as described above. In some examples, when theSOC of the power source approaches the minimum level and the auxiliarydevice would, if it continues to draw power, reduce the SOC to below theminimum SOC for a next heating cycle, the low state of charge becomesthe trigger event for the power-up sequence as described with regard toFIG. 2 . In some examples, the auxiliary device can continue to drawpower and operate as normal while the power-up sequence for the engineis performed.

In some examples, a minimum state of charge of the high voltage powersource is modified to enable the next heating cycle as described herein.In some examples, the modifying comprises elevating a minimum amount ofcharge to be held within the high voltage power source.

FIG. 4 . illustrates an example hybrid system power-up sequence 400, inaccordance with at least one of the examples described herein. As shown,a trigger event 210 is received. The trigger event 210 begins with theinitialization of the individual systems of the hybrid vehiclearchitecture. In some examples, the systems present in the hybridvehicle are the hybrid BECM 410, the engine control module (ECM) 420,the DC-DC converter 430, the e-machine 440, a device 450 connected tothe high voltage power source. In some examples, the BECM 410 and ECM420 may be the energy control module 240 and control module 220,respectively. In some examples, the power-up sequence described withreference to FIGS. 2 & 3 may be thought of simple exemplary examples ofthe exemplary power-up sequence 400.

In some examples, device 450 connected to the high voltage power sourceis the heating element for the after-treatment system. In some examples,device 450 connected to the high voltage power source is an inverter toprovide electrical power to external devices, such as power tools ordomestic appliances. In some examples, one or more systems areinitialized in parallel. For example, the BECM 410 and the ECM 420 maybe initialized in parallel, in response to the trigger event beingreceived. In some examples, at least two or more of: the BECM 410;auxiliary device connected to the high voltage power source 450; ane-machine 440; the engine control module 420; or DC-DC converter 430 maybe initialized in parallel, in any combination.

Returning to FIG. 4 , when the ECM 420 is online, the pre-charge phasebegins. In this phase, the ECM 420 sends a signal to the DC-DC converter430 to begin a pre-charge. In some examples, the DC-DC converter 430 iswoken first then instructed to begin pre-charge. In addition, the ECM420 sends a signal to the e-machine 440 to also begin initialization. Insome examples, the e-machine 440 may also be initialized in response tothe trigger event 210. In some examples, after the pre-charge iscompleted, the DC-DC converter 430 signals to the ECM 420 that thepre-charge is complete. After the completion of the pre-charge of theDC-DC converter 430, the ECM 420 determines the temperature of theafter-treatment system. In some examples, after determining that theafter-treatment system is below a threshold temperature, the ECM 420signals to the BECM 410 to close the e-switch (e.g., a solid-state basedrelay switch). In some examples, the BECM 410 reports the switch isclosed and that the hybrid battery is now connected to the high voltageelectrical bus terminal. In this way, the high voltage power source hasbeen brought online prior to the engine start.

After the high voltage power source is connected to the bus, the ECM 420signals to the auxiliary heat source connected to the auxiliary powersource 450 to begin the heating cycle of the after-treatment system. Insome examples, the after-treatment system may continuously report backto the ECM 420 data on the current heat cycle, including, but notlimited to, information regarding the start temperature of theafter-treatment system, the current temperature of the after-treatmentsystem, delivered power to the after-treatment system, an expected timeto reach a threshold temperature, an ambient temperature, a deltatemperature between the ambient temperature and the after-treatmentsystem. After the after-treatment system reaches the thresholdtemperature, a signal is sent to the ECM 420. In some examples, inparallel to the heating cycle of the after-treatment system, the ECM 420is preparing for an engine start, which may include initializing andengaging a starter motor to crank the engine. In this way, the auxiliarypower from the hybrid battery is provided before the engine has beenstarted and nominal running mode has taken place.

After the after-treatment system is at the threshold temperature, and arequest to crank the engine has been received, then the ECM 420 startsthe engine. In some examples, the engine start phase comprises a numberof steps that may be performed linearly or in parallel. For example, theECM 420 may request the DC-DC converter 430 to change from boost to buckmode (e.g., from a typical hybrid system voltage boost down to lowvoltage, 12V, buck), and also command the e-machine to nominal runstate.

In some examples, the hybrid power source also requires a modificationto the reserved power, or state of charge (SOC). In some examples, themodification comprises raising a minimum SOC at the end of a drive cycleor heating cycle to guarantee the power source can support a nextheating cycle. In some examples, the modified minimum SOC can bedynamically altered based on a number of contextual factors. In someexamples, the contextual factors comprise an ambient temperature, a timesince a last engine start-up, a delta temperature between thetemperature of the after-treatment system and the ambient temperature,an engine temperature, a maximum power output from the auxiliary heatsource, a maximum thermal energy output from the heat source, a targettemperature for the after-treatment system, or a state of charge of thepower source.

FIG. 5 shows a block diagram representing an electrical power controlsystem 500 for a hybrid vehicle. In the example shown in FIG. 5 , thepower control system 500 is for an exemplary mHEV system architecture,in accordance with at least one of the examples described herein. Shownin FIG. 5 is a belt-integrated starter-generator (BISG) 512, which is adevice that may produce torque and assist the engine in reducing theamount of work it has to do, or, in some examples, apply negative torqueto recover energy in the system. Colloquially, the BISG 512 may bereferred to as a motor-generator. The BISG 512 is integrated into thedrive train 510, along with engine 514, clutch 516, and transmission518. In some examples, the BISG 512 replaces a conventional non-hybridengine's low voltage (e.g., 12V) alternator. In some examples, the BISG512 transmits torque to the engine's crankshaft when it's operating as ahybrid drive motor, and the crankshaft transmits torque back to the BISG512 when it operates as a generator, converting kinetic energy from themoving vehicle back into electricity, operating as a conventionalalternator.

In some examples, the engine 514 has an exhaust system 520 comprising aneCAT 522. The eCAT 522 may be an eCAT with a start-up sequence, andheating cycle, as described herein. In some examples, the eCAT iselectrically connected to a DC-DC converter 530. In some examples, theDC-DC converter 530 provides 0-48V and 0-4 kW to the eCAT 522. In theexample shown in FIG. 5 , the DC-DC converter 530 is also electricallyconnected to a low voltage (e.g., 12V) battery and bus 540, which isconfigured to supply electrical power to one or more low voltageaccessories of the vehicle. In some examples, the DC-DC converter 530may be a separate DC-DC converter, i.e. a second DC-DC converter,separate to the DC-DC converter that is already part of a typical hybridvehicle system. In some examples, the DC-DC converter 530 is integratedinto the typical DC-DC converter found in HEVs (e.g., a 48v to 12v DC-DCconverter) to support the 12V vehicle system. In this way, there isprovided a single DC-DC converter 530 unit, with two outputs, one to the12V system and one to the eCAT 522 (of varied voltage). In someexamples, the eCAT 522 is electrically connected to a PWM switch, thePWM switch is controlled by an engine control module (ECM), and the PWMswitch is configured to modulate the power provided to the eCAT 522 orengine after-treatment system, as described above.

In the example shown in FIG. 5 , the power control system 500 comprisesa controller 560, e.g., an engine control module (ECM), in operationalcommunication with each of the BISG 512, the engine 514, the DC-DCconverter 530, and the eCAT 522, the low voltage battery and bus 540,the high voltage battery and bus 550 (e.g., a HEV power system), and apump 570. The pump 570 may be used to pump fluids such as air throughthe engine and exhaust system. In some examples, the pump is fluidlyconnected to the engine exhaust system to draw air from the atmospherethrough the eCAT 522 to transfer thermal energy from the heatingelements in the eCAT 522 to the catalyst.

The present disclosure is not limited to the set-up shown in FIG. 5 .For example, the controller 560 may be a stand-alone controller, or anyother appropriate controller of the hybrid vehicle. For example, thecontroller may, at least in part, be integrated with another controllerof the vehicle, such as a controller of the DC-DC converter 530.Furthermore, the controller 560 may be configured to operationallycommunicate with anyone or more of the vehicle components shown in FIG.5 , and/or any other appropriate components of the vehicle. For example,controller 560 may be a stand-alone controller configured tooperationally communicate with at least one high voltage accessory, anelectric motor-generator, and an eCAT, to control the electrical poweroutput of the high voltage battery 550.

While the example shown in FIG. 5 exemplifies the use of the controlsystem 500 for an mHEV, it is understood that the control system 500 maybe implemented on an appropriate type of hybrid vehicle, such as aplug-in hybrid electric vehicle (PHEV), having one or more high voltagecircuit components and an eCAT. System 500 shown in FIG. 5 is configuredto supply the electrical power output of a high voltage battery 550 of ahybrid vehicle to the eCAT 522, prior to the engine 514 being cranked,as described with reference to FIG. 4 above.

FIG. 6 illustrates an exemplary exhaust system 600 comprising an engine514 and an after-treatment system, such as an eCAT 522, in accordancewith at least one of the examples described herein. In some examples,and as shown in FIG. 6 , there is provided an air-box 610 connected to acompressor 620 to draw air from the atmosphere. The airbox andcompressor are fluidly connected to engine 514 and after-treatmentsystem 522 to transfer thermal energy from the heating element disposedwithin the after-treatment system 522 to the rest of the after-treatmentsystem 522 (e.g., from the eCAT to the catalyst).

In some examples, there is a diesel particulate filter 640 downstream ofthe after-treatment system 522. A diesel particulate filter (DPF) is afilter that captures and stores exhaust soot and is also itself anafter-treatment utilized to reduce emissions from diesel cars. DPFs havea finite capacity, the trapped soot periodically has to be emptied or‘burned off’ to regenerate the DPF. This regeneration process cleanlyburns off the excess soot deposited in the filter, reducing the harmfulexhaust emission.

In some examples, there is also provided a Selective Catalytic Reduction(SCR) 650 system. An SCR is another emissions control technology systemthat injects a liquid-reductant agent through a special catalyst intothe exhaust stream of engines, in particular diesel engines. Thereductant source is usually automotive-grade urea, otherwise known asDiesel Exhaust Fluid (DEF). The DEF sets off a chemical reaction thatconverts nitrogen oxides into nitrogen, water, and low amounts of carbondioxide (CO2), which is then expelled through the vehicle tailpipe 670.The DEF may be stored in a DEF tank 660. The DEF may be distributedthrough a number of pumps and valves 662-666, as shown in FIG. 6 .

In some examples, the exhaust system comprises a number of sensors 672to detect the flue gas containing Oxides of Nitrogen (NOx) and Oxides ofSulphur (SOx), to ensure the final emissions are within a regulationamount. Euro 5 exhaust emission legislation and Euro 6 exhaust emissionlegislation, have effectively made DPFs, DEF, and SCRs mandatory to meetthe emissions standards. However, future emission legislation, such asEuro 7, such technology along will not be sufficient. The systems andembodiments described herein may replace, or work in conjunction withDPFs, DEF, and SCRs and meet the future standards.

FIG. 7 illustrates a vehicle 700 comprising an engine and an exemplaryexhaust system 600, in accordance with at least one of the examplesdescribed herein. According to some examples there is provided a vehicle700 comprising an engine exhaust system 600 as described with referenceto FIG. 6 . In some examples, the vehicle further comprises a drivetrain 510 comprising a BISG 512, an engine 514, clutch 516, andtransmission 518. The exhaust system 600 may comprise an eCAT asdescribed above.

It should be understood that the examples described above are notmutually exclusive with any of the other examples described withreference to FIGS. 1-7 . The order of the description of any examples isnot meant to identify key or essential features of the claimed subjectmatter, the scope of which is defined uniquely by the claims that followthe detailed description. Furthermore, the claimed subject matter is notlimited to implementations that solve any disadvantages noted above orin any part of this disclosure.

Other variations to the disclosed embodiments can be understood andeffected by those skilled in the art in practicing the claimedinvention, from a study of the drawings, the disclosure, and theappended claims. In the claims, the word “comprising” does not excludeother elements or steps, and the indefinite article “a” or “an” does notexclude a plurality. The mere fact that certain measures are recited inmutually different dependent claims does not indicate that a combinationof these measures cannot be used to advantage. Any reference signs inthe claims should not be construed as limiting the scope.

The disclosure of this invention is made to illustrate the generalprinciples of the systems and processes discussed above and are intendedto be illustrative rather than limiting. More generally, the abovedisclosure is meant to be exemplary and not limiting and the scope ofthe invention is best determined by reference to the appended claims. Inother words, only the claims that follow are meant to set bounds as towhat the present disclosure includes.

While the present disclosure is described with reference to particularexample applications, it shall be appreciated that the invention is notlimited thereto. It will be apparent to those skilled in the art thatvarious modifications and improvements may be made without departingfrom the scope and spirit of the present invention. Those skilled in theart would appreciate that the actions of the processes discussed hereinmay be omitted, modified, combined, and/or rearranged, and anyadditional actions may be performed without departing from the scope ofthe invention.

Any system feature as described herein may also be provided as a methodfeature and vice versa. As used herein, means plus function features maybe expressed alternatively in terms of their corresponding structure. Itshall be further appreciated that the systems and/or methods describedabove may be applied to, or used in accordance with, other systemsand/or methods.

Any feature in one aspect may be applied to other aspects, in anyappropriate combination. In particular, method aspects may be applied tosystem aspects, and vice versa. Furthermore, any, some, and/or allfeatures in one aspect can be applied to any, some, and/or all featuresin any other aspect, in any appropriate combination. It should also beappreciated that particular combinations of the various featuresdescribed and defined in any aspect can be implemented and/or suppliedand/or used independently.

1-17. (canceled)
 18. A method of providing a heating cycle for anafter-treatment system of a vehicle, the method comprising: receiving astart trigger; initiating a pre-charge cycle of a DC-DC converter;determining a temperature of the after-treatment system; and in responseto determining that the temperature of the after-treatment system isbelow a threshold temperature, heating the after-treatment system usinga heating element until the after-treatment system reaches the thresholdtemperature.
 19. The method of claim 18, further comprising: starting anengine of the vehicle after reaching the threshold temperature
 20. Themethod of claim 18, further comprising: providing auxiliary power to oneor more electrical devices from a high voltage power source prior tostarting the engine.
 21. The method of claim 18, further comprising: inresponse to receiving the start trigger, initializing at least onevehicle system selected from a group consisting of: a battery energycontrol module; an auxiliary device; an e-machine; and an engine controlmodule.
 22. The method of claim 18, wherein the start trigger is atleast one of: a signal received from a key fob; a door of a vehicleopening; a signal received from a smart device application; an enginestart request; and detecting a proximity of a user.
 23. The method ofclaim 18, wherein the after-treatment system includes an eCAT, andfurther comprising: operating a pulse-width modulation (PWM) switch or aseparate DC-DC converter to modulate power from the high voltage powersource to the eCAT.
 24. The method of claim 18, further comprising:determining a plurality of contextual factors influencing the amount ofthermal energy provided to the after-treatment system.
 25. The method ofclaim 24, wherein the contextual factors comprise at least one of: anambient temperature; a time since a last engine start-up; a deltatemperature between the temperature of the after-treatment system andthe ambient temperature; an engine temperature; a maximum power outputfrom the auxiliary heat source; a maximum thermal energy output from theheat source; a target temperature for the after-treatment system; and astate of charge of the power source.
 26. The method of claim 18, furthercomprising: modifying a minimum state of charge of a high voltage powersource to enable a subsequent heating cycle of the heating element. 27.A system for an after-treatment system of a vehicle comprising controlcircuitry configured to: receive a start trigger; initiate a pre-chargecycle of a DC-DC converter; determine a temperature of theafter-treatment system; and in response to determining that thetemperature of the after-treatment system is below a thresholdtemperature, heat the after-treatment system using a heating elementuntil the after-treatment system reaches the threshold temperature. 28.The system of claim 27, wherein the control circuitry is furtherconfigured to: start an engine of the vehicle after reaching thethreshold temperature.
 29. The system of claim 27, wherein the controlcircuitry is further configured to: provide auxiliary power to one ormore electrical devices from a high voltage power source prior tostarting the engine.
 30. The system of claim 27, wherein the controlcircuitry is further configured to: initialize, in response to receivingthe start trigger, at least one vehicle system selected from a groupconsisting of: a battery energy control module; an auxiliary device; ane-machine; and an engine control module.
 31. The system of claim 27,wherein the start trigger comprises at least one of: a signal receivedfrom a key fob; a door of a vehicle opening; a signal received from asmart device application; an engine start request; and detecting aproximity of a user.
 32. The system of claim 27, wherein theafter-treatment system includes an eCAT, and wherein the controlcircuitry is further configured to: operate a pulse-width modulation(PWM) switch or a separate DC-DC converter to modulate power from thehigh voltage power source to the eCAT.
 33. The system of claim 27,wherein the control circuitry is further configured to: determine aplurality of contextual factors influencing the amount of thermal energyprovided to the after-treatment system.
 34. The system of claim 33,wherein the contextual factors comprise at least one of: an ambienttemperature; a time since a last engine start-up; a delta temperaturebetween the temperature of the after-treatment system and the ambienttemperature; an engine temperature; a maximum power output from theauxiliary heat source; a maximum thermal energy output from the heatsource; a target temperature for the after-treatment system; and a stateof charge of the power source.
 35. The system of claim 27, wherein thecontrol circuitry is further configured to: modify a minimum state ofcharge of a high voltage power source to enable a subsequent heatingcycle of the heating element.
 36. A vehicle comprising theafter-treatment system of claim
 27. 37. A non-transitorycomputer-readable medium having instructions encoded thereon forcarrying out a method, the method comprising: receiving a start trigger;initiating a pre-charge cycle of a DC-DC converter; determining atemperature of the after-treatment system; and in response todetermining that the temperature of the after-treatment system is belowa threshold temperature, heating the after-treatment system using aheating element until the after-treatment system reaches the thresholdtemperature.